摘要
采用力学性能、电导率测试、金相和电子显微分析技术,研究固溶-时效处理对Al-Zn-Mg-Sc-Zr铝合金板材组织与性能的影响。结果表明:Al-Zn-Mg-Sc-Zr合金板材的最佳热处理制度为(470℃,1 h,水淬)+(120℃,24 h);在此条件下,合金的抗拉强度、屈服强度、伸长率、硬度和电导率分别为587 MPa、564 MPa、8.95%、155HB和34.5%(IACS);固溶过程中,适当提高固溶温度或延长固溶时间,合金中过剩相逐渐减少,基体过饱和程度增加;时效过程中,固溶体析出η′(MgZn2)和η(MgZn2)相,随时效时间延长,晶内析出相η′粗化,晶界上平衡相也粗化,与此同时,晶界无析出带宽化;合金的高强度来源于微量Sc、Zr引起的亚晶强化、Al3(Sc,Zr)粒子和η′相的析出强化。
The effects of solution and aging treatment on the microstructure and mechanical properties of Al-Zn-Mg-Sc-Zr aluminum alloy sheet were studied by hardness,tensile tests,electric conductivity measurement,optical microscopy and electronic microscopy.The results show that,the appropriate heat-treatment regime of Al-Zn-Mg-Sc-Zr aluminum alloy sheet is solution treated at 470 ℃ for 1 h and water quenching,and then aged at 120 ℃ for 24 h.Under this condition,the mechanical properties of σb,σ0.2 and δ5,the hardness and conductivity reach 587MPa,564 MPa,8.95%,155HB and 34.5%（IACS）,respectively.As the increases of the solution temperature and time,the major remainders disappear gradually and the strength of the alloy is improved.During the aging process,η′ and η phases precipitate from the solid solution,with the increase of the aging time,the η′ and η phases are both coarsened,and so as the precipitate free zone（PFZ）.The high strength is mainly due to the subgrain strengthening caused by the addition of Sc and Zr,the Al3（Sc,Zr） particles and the precipitation of η′ phase.
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
2010年第11期2063-2069,共7页
The Chinese Journal of Nonferrous Metals
基金
国家民口配套项目(JPPT-115-2-948)
关键词
AL-ZN-MG合金
固溶
时效
组织
力学性能
电导率
Al-Zn-Mg alloy
solid solution
aging
microstructure
mechanical property
electric conductivity
